Auto merge of #2986 - micbou:fix-python2-builds, r=micbou

[READY] Do not update pip on Travis and CircleCI

Attempt to fix the builds on Travis and CircleCI.

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.circleci/config.yml

@@ -22,14 +22,14 @@ aliases:
   # Increase the version key to clear the cache.
   save-cache: &save-cache
     save_cache:
-      key: v1-ycm-{{ .Environment.CIRCLE_JOB }}
+      key: v2-ycm-{{ .Environment.CIRCLE_JOB }}
       paths:
         - ~/Library/Caches/Homebrew
-        - ~/.cache/pip
+        - ~/Library/Caches/pip
         - ~/.pyenv
   restore-cache: &restore-cache
     restore_cache:
-      key: v1-ycm-{{ .Environment.CIRCLE_JOB }}
+      key: v2-ycm-{{ .Environment.CIRCLE_JOB }}
 jobs:
   python2:
     <<: *common

.circleci/install_dependencies.sh

@@ -73,7 +73,6 @@ if [ -z \"\${PYENV_LOADING}\" ]; then
   unset PYENV_LOADING
 fi" >> $BASH_ENV
 
-pip install -U pip wheel setuptools
 pip install -r python/test_requirements.txt
 
 set +e

ci/travis/travis_install.sh

@@ -63,7 +63,6 @@ python_version=$(python -c 'import sys; print( "{0}.{1}".format( sys.version_inf
 echo "Checking python version (actual ${python_version} vs expected ${YCM_PYTHON_VERSION})"
 test ${python_version} == ${YCM_PYTHON_VERSION}
 
-pip install -U pip wheel setuptools
 pip install -r python/test_requirements.txt
 
 # The build infrastructure prints a lot of spam after this script runs, so make